just put your lips together
by airbefore
Summary: Under normal circumstances, she'd assume he was doing something as innocent as visiting the bathroom but she knows him too well for that. It's late, they're alone, and he's restless; the perfect conditions for him to wander off in search of trouble.


**Disclaimer:** All television shows, movies, books, and other copyrighted material referred to in this work, and the characters, settings, and events thereof, are the properties of their respective owners. As this work is an interpretation of the original material and not for-profit, it constitutes fair use. Reference to real persons, places, or events are made in a fictional context, and are not intended to be libelous, defamatory, or in any way factual.

_This exists because when you post dirty headcanons on Tumblr, people ask you to write them. _

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_... and blow_

He's not where she left him.

Beckett walks out of the break room, a coffee in each hand. The bullpen is quiet, the white noise of buzzing fluorescent lights all she can hear. It's late, almost midnight. She sent the boys home an hour ago, had attempted to make Castle go with them.

_Nope. You're here, I'm here._

She tried to hide the smile, rolling her eyes and pursing her lips while the boys made fun of them, a chorus of _aw_s and _isn't that so sweet_s following them all the way to the elevator. When the doors closed behind them, she'd lifted herself up onto the edge of the desk, sliding toward him until their thighs were pressed tightly together, and kissed him on the cheek, murmuring a soft thanks into the angle of his jaw.

They hit a wall ten minutes ago and she went for coffee, leaving Castle standing next to her desk, his arms lifted over his head in a deep stretch. But now he's gone, the pen he'd been flipping through his fingers for the past thirty minutes tossed haphazardly onto the middle of her blotter.

Beckett puts the rapidly cooling mugs on her desk and goes in search of him. Under normal circumstances, she'd assume he was doing something as innocent as visiting the bathroom but she knows him too well for that. It's late, they're alone, and he's restless; the perfect conditions for him to wander off in search of trouble.

A gentle squeaking catches her attention. She walks slowly down the aisle, eyes scanning the conference rooms for his shadow. The noise gets louder the closer she gets to Gates' office and Beckett swears under her breath, her steps quickening. She's going to kill him.

And then Gates will kill them both.

"What are you doing?"

Castle stops rocking and spins the chair around, his shoulders lifting in a shrug. "I thought a change of scenery might help get us moving forward again."

"And you thought Gates' office was the best option?" She crosses the room, stopping to stand in front of him, arms folded over her chest. "She'll freak if she finds out you were in here."

"If she finds out _I_ was in here?"

Beckett rolls her eyes. "She likes _me_."

"Fair point." He nods, reaching out to hook his right hand around her thigh. She stumbles when he tugs her forward, hands flying out to catch herself on his shoulders. "I'll go but first there's one thing I've always wanted to do in here."

"I am not having sex with you on her desk."

"You know, I don't think anyone observing us from the outside would ever guess that _you're_ the one with the filthy mind." He tugs again and she falls into his lap a little more easily than she should but it's late and she's tired and the idea of pressing herself against him and relieving some of the tension riding low in her back is extremely appealing at the moment. "I never said anything about sex."

"Then what?"

He answers her with a kiss, one hand sliding up her thigh and the fingers of the other twining through her ponytail. Beckett opens her mouth immediately, moaning softly when he sweeps his tongue over hers. She loses herself in the kiss, turning to straddle him, her knees at his hips and calves tucked between his thighs and the arms of the chair.

Castle slips his hand into the gap at the back of her pants, fingers kneading her ass. The chair squeaks in time with the roll of her hips, a tight little rhythm she can't control. His mouth drops to her neck and Beckett groans, hands roaming over his chest and stomach. She grinds herself into the bulge in the front of his pants when he bites her collar bone, the seam of her jeans pressing hard against her clit.

Sharp teeth sink into her neck and Beckett relaxes her thighs, dropping her full weight onto his lap. Biting his ear, she gasps when she rubs against him in just the right way, pleasure burning like flashpaper at the base of her spine. The orgasm ends almost before it started, nothing more than an opening act. Castle leans back and even through the shadows, she can see the smirk on his face. "Did you just come?"

"Shut up."

She climbs off his lap and spins toward the window, reaching out to tug the string. The slats flip closed with a sharp crack. Turning to face him again, Beckett moves to stand between his spread legs and stares down at him for a moment before bending over and reaching for his belt buckle.

"I thought you said no sex."

"I did." Sinking down to her knees, she pulls his erection free, smirking when his eyes go wide. "But there's one thing _I've_ always wanted to do in here too."

Castle curses out her name when she opens her mouth, tongue swirling lightly over his tip. She takes her time, teasing him with long licks and slow strokes, smiling when she sees his fingers turning white as he grips the arms of the chair.

"_Fuck_, you are so good at that," he groans, one hand moving to stroke along the length of her shoulder.

Beckett smirks. "I know," she says before taking him fully into her mouth, right hand twisting around his base as she bobs.

Castle surrenders his grasp on the chair and grabs her hair, wrapping the rope of her ponytail around his fist and tugging. Moisture floods her underwear when he starts to thrust into her mouth, shallow pumps of his hips that rock the chair and make her moan. The wheels scrape against the plastic floor protector as the chair moves, the hinges squeaking and leather sighing.

"Beckett," he grunts, hand slipping into the collar of her shirt and blunt nails digging into the base of her neck. "I'm gonna -"

Stopping for just a moment, she smiles at him and strokes her hand up and down, giving a little twist around his tip. "I know." Breathing deeply through her nose, she leans down over him again, taking as much of him into her mouth as she can. He hits the back of her throat and she pauses, lifting her eyes so she can watch his face when she swallows. She loves watching him. Castle's head hits the back of the chair and he groans, the toes of his shoes knocking into her knees as his feet twitch.

He comes on a curse, hot and fast spurts that stick to her tongue and coat her cheeks. Beckett swallows and eases off him, letting him slide slowly out of her mouth. Castle stares at her with hazy eyes as she tucks him back into his pants, closing the zipper and fastening the button. Bracing her hands on his knees, she pushes to her feet and then leans over to kiss him, running her fingers gently through his hair.

"We can go back to work now."

Castle's hands grip her waist when she turns toward the door, his fingers pressing hard into her stomach as he yanks her back. She lands in his lap, her laughter quickly turning into a moan when his hand slides between her legs, two fingers pressed tightly to the damp crotch of her pants.

"You do know that there is no way in hell that's going to happen, right?" He circles his fingers and laughs when she whimpers soflty, nodding. Castle kisses her neck, tongue dipping into the hollow behind her left ear. "Thought so."

He goes for the button on her pants and she grabs his wrist, halting his movement. "Not here." Beckett stands, tugging her clothes back into place and smoothing down her hair. "Let's go."

"But there are so many things I want to do to you in here now," Castle whines.

Beckett re-opens the blinds and walks toward the door, tugging her clothes back in place. "Guess you should have thought of that before you wasted your 'one thing' on a kiss, then." Opening the door, she looks back over her shoulder and waves a hand at him. "Don't forget to put the chair back how you found it. And straighten her desk. It looks like someone had sex up against it."

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_Thanks for reading. Your thoughts and comments are always appreciated. _


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